Fix broken CDTestFramework

Avoid crash in BulletWorldImporter, ignoring 'invalid' constraints between two static bodies
Use a bitfield for btCollisionObject::CollisionObjectTypes (to allow custom types that are derived from build-in types such as btRigidBody)
Revert/improve softbody debug rendering

src/BulletCollision/CollisionDispatch/btCollisionObject.h

@@ -128,12 +128,13 @@ public:
 	enum	CollisionObjectTypes
 	{
 		CO_COLLISION_OBJECT =1,
-		CO_RIGID_BODY,
+		CO_RIGID_BODY=2,
 		///CO_GHOST_OBJECT keeps track of all objects overlapping its AABB and that pass its collision filter
 		///It is useful for collision sensors, explosion objects, character controller etc.
-		CO_GHOST_OBJECT,
-		CO_SOFT_BODY,
-		CO_HF_FLUID
+		CO_GHOST_OBJECT=4,
+		CO_SOFT_BODY=8,
+		CO_HF_FLUID=16,
+		CO_USER_TYPE=32
 	};
 
 	SIMD_FORCE_INLINE bool mergesSimulationIslands() const